This proposal is to purchase an image analysis system to be shared by a multidisciplinary group of PHS-funded investigators engaged in biomedical research. Dr. Bottenstein's project studies the proliferation of oligodendrocytes in vitro. A novel growth factor is being isolated and characterized that markedly stimulates the production of oligodendrocytes in neonatal rat brain cultures. 3H- thymidine autoradiographs will be correlated with differentiation- specific antigen profiles of cells to identify target of the growth factor. Cryostat sections of developing rat brain stained with monoclonal antibodies to the growth factor will detect the presence of immunoreactive endogenous factors. Finally, morphological development of mature oligodendrocytes from precursor cells will be followed with time-lapse analysis. Dr. Hulsebosch's project studies the effects of Nerve Growth Factor (NGF) deprivation on development of sprouting and synaptogenesis of primary afferent fibers in rat spinal cord using immunocytochemical and ultrastructural methods. The distribution of 125I-NGF, NGF receptors, and NGF mRNA will be analyzed in newborn, young, adult, and aged rat CNS and PNS. Dr. High's first project studies the immunocytochemical localization of monoamine oxidase A and B in normal human brain compared to several neurological syndromes, including Parkinson's and Alzheimer's disease, schizophrenia, and chronic alcohol abuse. The second project characterizes and quantitates catecholamine synapses on primate spinothalamic tract (STT) cells with light and EM methods. Also, mapping of brainstem neurons that project to the thalamus will be done with fluorescent tracers. Dr. Carlton's projectinvolves light and EM analysis of terminal inputs onto identified primate STT cells. After characterization of the normal terminal population, immuno-staining will identify and show the distribution of serotonin, substance P, and enkephalin terminals on STT cells. The sources of these terminals from descending, primary afferent, or intrinsic neurons will be evaluated. Dr. Chung's project studies the organization of primary afferent and propriospinal fibers in cat spinal cord. The number and termination sites of unmyelinated primary afferent fibers in dorsal funiculus will be determined. The number of propriospinal fibers in each funiculus will also be analyzed. The projects described in this application are relevant to various aspects of normal development, aging, demyelinating diseases, neuronal regeneration, mental and motor disorders, and pain mechanisms.